ultrafast fiber laser
Credit: Pixabay/CC0 Public Domain

Scientists have developed an ultrafast fiber laser that delivers an average power more than 10 times what is available from today’s high-power lasers. The technology is ready to enhance industrial-scale materials processing and paves the way for visionary applications.

Michael Müller, a Ph.D. student of Prof. Jens Limpert from the Friedrich Schiller University’s Institute of Applied Physics and the Fraunhofer Institute of Institute for Applied Optics and Precision Engineering in Jena, Germany, will present the new laser at the all-virtual 2020 OSA Laser Congress to be held 12-16 October 2020. The presentation is scheduled for Tuesday, 13 October 2020 at 14:30 EDT.

High power without the heat

In lasers, waste heat is produced during the process of light emission. Laser geometries with an enormous surface-to-volume ratio, for example, fibers, can dissipate this heat well indeed. Hence, the average power of around 1 kW is obtained from the present high-power lasers. Beyond this power, the heat load degrades the beam quality and represents a limit.

To circumvent this restriction, the research group around Müller and Limpert made another laser that externally combines the output of 12 laser amplifiers. They indicated that the laser can produce a 10.4-kilowatt average power without degradation of the beam quality. Thermographic imaging of the final beam uncovered marginal heating. In this way, power scaling to the 100-kilowatt level could be refined by adding even more amplifier channels.

In the future, high-power combined lasers not only will accelerate industrial processing but also enable formerly visionary applications such as laser-driven particle acceleration and space debris removal – said, Müller.

The investigation of novel applications at that power level as well as the transfer of the laser technology to commercial systems is ongoing within the frame of the Fraunhofer Cluster of Excellence Advanced Photon Sources (CAPS), which foremost involves the engineering of the laboratory setup into a rugged design. On the research side, the team in Jena now focuses on multicore fibers that offer the potential to deliver even superior performance in simpler and smaller systems.

More information: OSA Laser Congress